Invertebrates as bioindicators o

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					Fall 2007- EEES 47/57/7740 (Mayer); Sept 21, 2007 Aquatic Ecology Lab: Field trip Ten Mile Creek, Harroun Community Park, Sylvania, Ohio. Title: Collection of Macro-invertebrates from riffles and pools of Ten Mile Creek, Sylvania, Ohio. Background: Biological monitoring is a relatively simple and cost-effective method of determining the quality of rivers and streams. Organisms may give a more rapid assessment of stream quality than direct measurements of chemical attributes such as pH, dissolved oxygen, or phosphate concentration. Further, chemical measurements must be repeated many times because they vary widely in response to short term fluctuations in water flow, position in the stream, etc, whereas the biological community can be considered to integrate conditions over time. Relatively sedentary small organisms, such as macroinvertbrates however, need only be sampled once to reveal the occurrence of pollutants, since they have to be able to withstand the poorest water quality conditions likely to occur during their lifetimes. Early efforts at biological assessment focused on single or groups of indicator species that were either very tolerant or very intolerant of degraded habitat. This approach was built upon by use of community-level indices such as: diversity indices, species richness and species evenness. These indices assume that undisturbed communities are more diverse than disturbed ones, which may not always be a good assumption (refer to your intro ecology notes). The most recent approach has been to combine biological, chemical and physical parameters into an Index of Biotic Integrity (Karr 1991). Originally stream fish were used as the biological indicator group. EPA now uses Rapid Bioassessment Protocols. Both of these methods can be applied to any taxonomic groups, or combinations of taxonomic groups. We will collect macro-invertebrates (organisms which lack a backbone and are visible to the naked eye) from two habitats in a local steam and calculate several community indices, an Invertebrate Quality Index (IQI), and further compare the invertebrate assemblage from the stream to that collected at Allen Lake. Harroun Community Park is an approximately 12 ha park owned and managed by the City of Sylvania, Division of Parks and Forestry. It is located in a ravine-like setting along the banks of the Ten Mile Creek, the headwater stream of the Ottawa River. The Ottawa River, in turn, drains a 446 km2 low-gradient basin in northwestern Ohio and discharges into Maumee Bay and western Lake Erie.

Stream Sample collection: Group supplies: --Waders --Kick seines (2) --D-nets (2) --White pans (4) --Forceps --Magnifying glasses --Sample jars (12) --Lots of labeling tape

--Ethanol --Wash bucket --Digital camera --Neoprene gloves --Water quality probe Individual supplies: --Warm clothes that can get dirty --Warm gloves for after sampling

In stream procedures: Using kick seines, we will sample the taxonomic composition of the aquatic invertebrate community in two habitats („riffles‟ and „pools‟) in Ten Mile Creek, Sylvania. Pairs of students will collect 3 ‘official’ samples from each habitat type. One student will stand behind the net while a second student will gently disturb the substrate in front of the net for ~1 minute. Try to avoid getting lots of debris or large rocks in your sample. The contents of the net will be transferred to the gray wash bucket, sieved then placed in a labeled jar with ethanol. These samples will be processed in lab on Oct 26th. Other students will use D-nets to sample a variety of habitats. The live content of these samples will be examined streamside for you amusement and pleasure. At the same time, we will measure in-situ water quality parameters such as dissolved oxygen, pH, conductivity, and temperature using an automated water quality probe (Pasco or YSI.). The data collected today will then be used to accomplish the following objectives:    Characterize differences and similarities between the riffle/pool/lake habitats. Compute an Invertebrate Quality Index (IQI) for the stream as a whole. Compare the invertebrate communities collected in a stream and a lake

Fall 2007- EEES 47/57/7740 (Mayer); Oct 26, 2007 Aquatic Ecology Lab: Benthic invertebrate sample processing. Title: Analysis and comparison of Lake and stream zoobenthos Each student will be responsible for processing 2 samples (one lake and one stream) during class and calculating the indices described. There will be 3 samples from 2 stream habitats (pool & riffle) and 2 samples from 3 lake habitats (gravel, reeds, lilies) Supplies needed for lab: --2 samples in jars --white pan --Forceps --Random grid sheets ~6 small Petri dishes

--Invertebrate guide --Data sheets (2) --Microscope --<500 μm sieve

In lab procedures: --Rinse your sample with water through one of the sieves provided. Save the ethanol. --Place a grid sheet (provided) in a white pan and pour your sample in with the minimum amount of water to submerge all contents. Distribute contents evenly using forceps or gentle shaking. --Remove all organisms from the grid section labeled “1” in your pan- even the wee ones. Place them into Petri dishes. You can try to separate them into groups based on overall appearance. Proceed to section two, etc…. till you have at least 50 organisms. When you reach 50, finish that grid cell and stop. If a bug in on the line between cells, exclude it. Place the rest of your sample back in the jar with the saved ethanol. --Repeat with your second sample. Keep the Petri dishes from your 2 samples separate. --Use a microscope and the guides provided to identify all your organisms to the lowest practical group. Count and record on the provided data sheet. Keep and record your two samples separately. Fill in a separate data sheet for each of your samples. --You are not expected to identify your bugs to species, but to estimate species richness you should split all your organisms into groups that you think are the same species (even though you wont know exactly what they are) and count this number for each sample. --Ask your instructors for help if you are having trouble with identification. --Calculate standardized (expected total sample) number of organisms using the formula: Standardized # (expected whole sample) = # organisms found * (#cells counted/total # cells) --Turn in your two completed data sheets before leaving. --If you get done really fast try doing an extra sample! After lab your TA will compile data from all the samples and post this information in the form of an Excel spreadsheet on the My UT course website. You will need these data to complete your lab report.

Lab Report: Analysis and comparison of Lake and stream zoobenthos Due on 2 Nov 2007 Use the compiled data to complete your report. Your report should consist of the following sections (use appropriate headings): 1. A couple of paragraphs of Introduction giving important background information on: 1) habitat factors that shape the invertebrate community in lakes vs. streams and 2) the use of aquatic macro-invertebrates as indicators of stream quality. Also, state the Purpose of your report. 2. A very brief description of the Field Sites and the collection and processing Methods we used. 3. A Results section a. Present a table with water quality information for each of the two stream habitats and the open water lake habitat and briefly discuss plausible reasons for obvious differences. b. Present a table listing the compiled taxonomic composition based on standardized numbers of each habitat (6 total habitats) and the relative abundance of each taxon in the sample. Relative abundance is calculated as % of total organisms. c. Calculate the Invertebrate Quality Index (IQI) for this reach of Ten Mile Creek using compiled data for the riffles and pools. The IQI gives the stream a quality rating between 0 (no invertebrates present) and 50. Instructions for calculating IQI values were included in your lab data sheet. d. Combine the data from the 2 river habitats and combine the data from the 3 lake habitats. Compare the number and taxonomic composition of benthic invertebrates in the lake and the stream. Include appropriate graphs or tables. 4. . A Discussion section: Interpret each of your results in the context of aquatic ecology in general based on your knowledge from this and other courses. 5. References cited (only list references you cited in the report). Some useful references and websites:  Karr J.R. 1991. Biological integrity: a long neglected aspect of water resource management. Ecological Applications 1:66-84  Merritt, R. and K. Cummins 1984. An introduction to the aquatic insects of North America. 2nd Edition. Kendall-Hunt, Dubuque, Iowa.  Needham, J. and P. Needham. 1962. A guide to the study of fresh-water biology. Holden-Day, San Francisco.  Pennak, R. 1978. Freshwater invertebrates of the United States. 2nd Edition. Wiley & Sons, New York.  Sanders, R.E. 2001. A guide to Ohio streams. Ohio Department of Natural Resources, Columbus, Ohio.  Biological Monitoring of Freshwaters- Benthic Macroinvertebrates- Background, Diversity & Biotic Indices

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Science Junction Water What-ifs Macroinvertebrates Tim's Aquatic Macroinvertebrate ID Links VCSU Macro-Invertebrate Lab - Digital Key to Aquatic Insects of North Dakota Various freshwater snails. North American Benthological Society. United States Environmental Protection Agency.

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